Alert archive / Arizona / Severe Thunderstorm Watches in 2016

Severe Thunderstorm Watch 424

July 29, 20164 counties in Arizona

The Storm Prediction Center issued this severe thunderstorm watch at Jul 29, 2016, 4:58 PM MST for 4 counties in Arizona. It was in force for 6 hr.

The area

The outline as issued.

The facts

Issued
Jul 29, 2016, 4:58 PM MST (23:58 UTC)
Expired
Jul 29, 2016, 11:00 PM MST
In force
6 hr
Issued by
the Storm Prediction Center
Largest hail expected
1 in
Strongest gust expected
60 kt

Counties Maricopa County, AZ, Pima County, AZ, Pinal County, AZ, Santa Cruz County, AZ

The radar

The Phoenix radar (KIWA), 90 km from the middle of the area, began a volume at 00:00 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

What SPC expected

The probabilities SPC published with the watch, for the watch area over its life.

Two or more tornadoes
5%
One or more EF2 to EF5 tornadoes
2%
Ten or more severe wind reports
30%
One or more gusts of 65 knots or more
10%
Ten or more severe hail reports
5%
One or more hailstones of 2 inches or more
5%
Six or more combined severe hail and wind reports
50%

Warnings issued inside it

17 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.

IssuedProductOfficeCountiesLasted
Jul 29, 5:07 PM MSTSevere Thunderstorm WarningTWCPima53 min
Jul 29, 5:16 PM MSTSevere Thunderstorm WarningTWCPima59 min
Jul 29, 5:43 PM MSTSevere Thunderstorm WarningTWCPima62 min
Jul 29, 5:59 PM MSTSevere Thunderstorm WarningTWCPima46 min
Jul 29, 6:01 PM MSTSevere Thunderstorm WarningTWCPima74 min
Jul 29, 6:07 PM MSTFlash Flood WarningTWCPima113 min
Jul 29, 7:43 PM MSTSevere Thunderstorm WarningPSRMaricopa32 min
Jul 29, 7:46 PM MSTSevere Thunderstorm WarningPSRMaricopa, Pinal29 min
Jul 29, 8:11 PM MSTSevere Thunderstorm WarningPSRMaricopa19 min
Jul 29, 8:21 PM MSTSevere Thunderstorm WarningPSRMaricopa39 min
Jul 29, 8:24 PM MSTSevere Thunderstorm WarningPSRPinal36 min
Jul 29, 8:29 PM MSTSevere Thunderstorm WarningPSRMaricopa, Pinal31 min
Jul 29, 9:00 PM MSTSevere Thunderstorm WarningPSRMaricopa45 min
Jul 29, 9:16 PM MSTSevere Thunderstorm WarningPSRMaricopa44 min
Jul 29, 9:59 PM MSTSevere Thunderstorm WarningPSRMaricopa31 min
Jul 29, 10:15 PM MSTSevere Thunderstorm WarningTWCPima60 min
Jul 29, 10:29 PM MSTSevere Thunderstorm WarningPSRMaricopa31 min

Discussions around it

SPC mesoscale discussions over the same counties from four hours before the watch to its end.

The nearest sounding before it

Phoenix, AZ (KPSR), launched 12:00Z, 12.0 hours before the alert went out and 95 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Phoenix, AZ at 12:00Z on 2016-07-29Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 911 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Phoenix, AZ at 12:00Z on 2016-07-29The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -66 square meters per square second.1939Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
911 J/kg
Mixed-layer CIN
-339 J/kg
Mixed-layer LCL
2440 m above ground
0-6 km bulk shear
20 kt
0-1 km storm-relative helicity
-66 m²/s²
0-3 km storm-relative helicity
-29 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 29, 3:32 PM MSTMesoscale DiscussionSPCCochise, Gila, Graham, Greenlee, Maricopa, Pima and 2 more2 hr
Jul 29, 4:51 PM MSTMesoscale DiscussionSPCPima, Pinal, Santa Cruz54 min

Nearby

Severe Thunderstorm Watches in Arizona, 2016Every severe thunderstorm watch in 2016

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.